Click here for a lecture that presents empirical support of Granovetter’s seminal 1973 paper on the importance of weak ties in social networks.
In short, Prof. Jari Saramaki shows using mobile communication networks that weak ties are critical for the gluing together of social networks on a large scale, while strong ties give rise to local clusters of closely tied together friendship groups. These findings are interesting because they support the two hypothesis put forth Granovetter: (1) that there is a transitivity of strong friendship ties, i.e. if A knows B, and B knows C, then there the probability that A knows C is increasing in the strength of the tie between A and B, and (2) that removing a weak tie has a greater impact on the shortest path of the network than has the removal of a strong tie. For more, see lecture: here.
